X.org X11 Server TigerVNC integer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.3$0-$5k0.00

Summaryinfo

A vulnerability was found in X.org X11 Server. It has been classified as problematic. The impacted element is an unknown function of the component TigerVNC. The manipulation leads to integer overflow. This vulnerability is uniquely identified as CVE-2025-49176. Local access is required to approach this attack. No exploit exists.

Detailsinfo

A vulnerability was found in X.org X11 Server (unknown version) and classified as problematic. This issue affects an unknown code block of the component TigerVNC. The manipulation with an unknown input leads to a integer overflow vulnerability. Using CWE to declare the problem leads to CWE-190. The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

A flaw was found in the Big Requests extension. The request length is multiplied by 4 before checking against the maximum allowed size, potentially causing an integer overflow and bypassing the size check.

The advisory is shared at access.redhat.com. The identification of this vulnerability is CVE-2025-49176 since 06/03/2025. The exploitation is known to be easy. An attack has to be approached locally. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 240228 (Fedora 42 : xorg-x11-server-Xwayland (2025-b4d521f084)), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at Tenable (240228) and EUVD (EUVD-2025-18503). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 7.3
CNA Vector (redhat): 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Integer overflow
CWE: CWE-190 / CWE-189
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 240228
Nessus Name: Fedora 42 : xorg-x11-server-Xwayland (2025-b4d521f084)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

06/03/2025 🔍
06/17/2025 +14 days 🔍
06/17/2025 +0 days 🔍
06/30/2025 +13 days 🔍

Sourcesinfo

Vendor: x.org

Advisory: access.redhat.com
Status: Not defined

CVE: CVE-2025-49176 (🔍)
GCVE (CVE): GCVE-0-2025-49176
GCVE (VulDB): GCVE-100-312737
EUVD: 🔍

Entryinfo

Created: 06/17/2025 18:12
Updated: 06/30/2025 11:27
Changes: 06/17/2025 18:12 (61), 06/17/2025 19:40 (1), 06/21/2025 17:35 (2), 06/23/2025 09:21 (1), 06/30/2025 11:27 (4)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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